Hydraulic plastic press



L.S.HUBBERT HYDRAULIC PLASTIC PRESS Oct. 2l, 1930.

Filed Jan. 17, 1928 5 2 sheets-sheet -2 Stacy, and `particula'rly relates to an iin,-k

Patented @ctt 21, 1930 LESLIE s.y HUBBERT, oFEnrsoNyoHio, Assieumi 'do brin HYDRLIoraEsS FAGTURNG COMPANY, 10F 4IYIGUN GIL-311113:, .OHIQ v, l

' 'maremma rms'ificiasss vThis invention relates to .lirnprovementsin the type of Vpress disclosed'in PatentNo; 1,567,7 66, granted December 29, 1925, to T. F.

.l proved mechanism v:for tilting the upperpress headla'nd for givingthe r`lower'press tablea sliding movement -,into and out of its operative positon. rDhese two `movements are to bring the head and table into a position more accessible to the operator.

The mechanism for producing both of these desired movements comprises double acting hydraulic cylinders of thedi-Herential type, and hydraulic piping" is connectedjto each so that a Z'ccxnstant pressure is exerted'fagainst the Vsmall end of the rains whfi'chfslide in the cylinders.' lMeans is provided whereby theseV memberscanbe mOVed /ou-t'fo'f vthe 'pressing position by means of pressure 'fadinitted through an automatic valve Ato the'y large' end In many respects, thel type 'O' pressto which'. the invention applicable rn-aybek widely varied,v but vthere is 1 shown herein a press having a ba'se A supi-porrtiiig-'the platen B, which yis movableupward to bringthe dies carried. thereby .in contact lwith ain *upper 'y Y,

sitlon, where rt will be iaccess blet'o theoperator, fluid under pressure will 'fbfe admitted,

press member supported bytliele'adfC-of the press. The upper and lower members of the press frame arerpreferably connectedby four strain rodsD; VvThere may also be pro! vided pullba'ckV orf kstripping 'cylinders E which return the platen B to `its lowermost position. These partsare for may be substantially similar'to those shown' in the above,

entitled patent, or ni'ay loe-varied as desired.

The lower pressimember comprises a table 1 which :is adapted to .slide onigfudeways f2 carried by the vertically movable platen'B.

This table has a ycylinder formed integra-1 therewith, the cylinder opening projecting through the. table 'andbeng Alinedwith a tubu-larniernber 4;' vl*Opposed'endsfof L l v ind-er are closed by paclingsi` and 18 respete Y tive-1y heldf iin place by gland nuts f5 and it win Lne-noted that the Yplatea lB isr'aiso fa support-upon vwhich Avtfheft'able 1 iscarriefl.

Afhollow piston rod i9 is held' Ziii-1a support` and has lock nuts 11 and l'fscrew threaded thereon on each side of the inerlrber 10.'

hollow piston ro d .passes throng-han opening Tdimitir? "ing'inen'iber 10carri'ed` by fthepifess lfranse v 9 in the .gl-'and' 5, lfand at 'its inner -'endv li-'s screw -A threaded at 18 into a piston head 114 'provi-ded l with suitable packing 15 between th'efouftsi de smeer .and al@ .wan .or the Hollow @starr-od l 4.- fA pipello 'passes@scientifically'through the, piston v rod to resultant-spambetweenfthe pistonrodamd thepi-p ,andfsuifaround the pipe at its outer errdl,i "-At its inner f y 7oy A endft'hejpipe 1-6is screw Athreaded iartoftli'e piston head 14 A andthepipe connects witha passageway 18 `through said-piston which opensnto chamber 19 at tiremier l endy or the cylinder 121. 'Aqpipe' 12o, passes threugktlie"wallfof the pistonrorllefoutside' 'opening 2i which' communicates with chamber fof thelcyliirder L lon the outside fof.

thejpiston ro'dQu v A y n. t v A the position shownnin Figuregthetagble isin 'its inner or 'operative position;7 and lit f is desired to slide the table Et e outer 'po- .se Y

to 'the .pipe 16 :and passage ifsrrftothe e1f1amo ber 19. :Since the piston rodQ pisto 14C are khel-d against endvwise infoyefneut, theL pres sure'or the ftl'uid will cause the-tablet@ il'nov'e.

toward the left of Figurev 2 to its oiitei posi',-

tion. When the table is to be-liioyje'dA back into the innerV pioszftixm,op:fessurey will be 1repiston rod 9, vand -wiflfl' eserttitspres'sure i 'i half the area of 'thehead formed bythe chamber 19. The table will therefore be returned f to its inner or operative position. Y Dueto the fact thatthe piston rod passes through one end of the cylinder the effective yarea of that endis less than that of the other so that pres- :sure mayV be constantly contained in the pipe 20, since, when pressure is admitted to the pressure entering through the pipe 2O tends .to return the'pipe to its inner position. It is A to benotedrthat while tlie'table yl is normally Vdisposed betweenthe platen and thev press pipe 16, it will act against a head Vsubstantially twicelasfgreat as that'of theother head, Vso that the tablemay be moved-outwardly,

notwithstanding the fact that the fluid under fhead C, jitis adaptedto be moved laterally l toward the front of the press to a projected position.V `The means for thus moving theV table are connected to the support upon which the table slides; at-the rear end only of the press sothat said means do not in any way 1nterfere'with thedopperator who stands Vat @the front of the machine.

' ,Th'e present invention also comprises a difl p Y ferent meansffor operating thepupper tiltingl platen orfpressfhead., Ardouble acting cylinder- 24 is provided withA a piston rod25, which v carries intermediate its ends aV member 26 having ka slot 2,7l therein. Apin 28 works inV v this slotandis'carried by a crank arm 29 which is fastenedto thetrunnion 30v of the tilting-platen head.v Itisobvious that a right l line movement oftheniston rod 25 will result in rotating the. platen head BlV through the desiredl angle, which is preferably about ninety degrees.; n y v y `It is obvious that any desired form of 'stops may be employed to limit Vthe movements of the table and the Vtilting `head in eachV Vdirec*- tion.4 1Both thetable and' the tiltinghead are formedwith T-slots'in the usualmanner for theV attachment of dies, and they maybe equipped with any desired form of knockout devices. Y The sliding table Vmay bevequipped with adjustable gibs for taking up lost mof tion or wear. The movable platen which car'- fries the Vtable and themainram are returnedl to'l'ower position by gravity, assisted by the auxiliary hydraulic cylinders Although not strightly a portion of the present invention, itmay be notedfthattheY y presentpress is automatically controlled by a motor-driven valve which Vcauses .the follow` ing operations vto talieplace insequence dur- Y ing one complete revolution ofa motor-driven cam shaft.

Y `l. The pressV head and'rsliding'f'tableV are moved'into pressing position, sinceat this time the large-,'.end atreach differential auX- iliary ram' is Aconnected -to the exhaust, thus allowing the-pressureto act onftheop'posite or 'small end o f the rams.

2. `lheifyalvethereuponstops and afterif'a."

final inspection the operator trips the autooperatingcam'shaft.

matic lever and thecycle proceeds automatically. 1

3. Steam is admitted to the chambers of the dies.

l 4;; The dies are closed and the main rainv moved upwardly under low hydraulic pressure.` W'

I `5. High hydraulic pressure appliedto i Y the system.

9. During the opening` offtheipressyhy;

Vdraulic pressureis appliedto revolve'the head andislide the tableout ofY pressing position so. thatthe'operator may quicklyremove the finl ishing pieces, cleanthe diecavities., and place inserts andraw moldingmaterlials for the starting ofthe next operation.V In each case the operation is initiated'bytrippin-ga leverwhich closesa-n electrical circuit, and

starts thervalve motor, The duration of the'f Y entire, cycle is Vregulated proper gearing provided for the-motor shaft fand the valve It is th-usapparent Ihat theipresent tion canbefapplied to'ia press of this character v 1 in order to perform the desired operations at thedesired point'in the cycle of operation of tion @may :be applied to pres'sesfofA different characters which; may operate on ysomewhat dierent principles, andthatvvariousidetails of constructionV and' arrangement Canjjfbe changed without in any departing -fr'om the spirit of theinvention. It is particularly Vto bewnoted that theinvention is to bexregarded as limited only by the scope of the ap-V i Y no pended claims.l .a l.Iclaim asm'y invention: 'a Y Lilnj a molding press,4 the. combination with a supporting framework, of. 4a support mountedon said framework, a tableslidably mounted von the support, a differential hydraulic cylinderfhaving opposed ends rigidly carried by said table,a piston mountedin the'cylinder, a hollow piston rod rigidly connected tothe'piston andto said support, Vsaid piston' Arodr passing -through -one `end of .the cylinder whereby the eective area thereof isless than that of theoppositeend,a pipe Y connected to lone side of the piston and communicatingwith the'cylinderfon the other siderof the/piston for admitting fluid under pressure tothe cylinder onthat side of the piston, said pipe being concentrically located fwithin the hollowv piston rod to forinfafresiilt'- ant space between thepipe and thefwal'lof Y the rod, saidrodbeingprovided with an l0() the press. It is also apparent thatthe lnven-.xf

Y mounted on the support and normally disopening communicating with said space andv vwith the cylinder on the side of the piston opposite that with which said pipe communi-r cates, means closing the ends of said space, and means for admitting fluid under pressure to said space. Y

2. In a molding press, the combination with a supporting Vframe, of'a stationary press head carried by the framework, a reciprocatory platen mounted for reciprocation with respect to vthe framework, a" support mounted on the platen, a table slidably passing through the rear end of the cylinder whereby the effective area thereof is less than that ofthe opposite end, Vmeans for admitting fluid under pressure to the cylinder on one side of the piston andmeans forvadmit# ting iiuid under pressure to the cylinder on the other side of the piston. A y

3. In a molding press, the combination with a supporting frame, of a stationary upmounted in the cylinder, a hollow piston rod rigidly connected to the piston and to said support and extending through one end Of the cylinder whereby the effective area thereof is less than that ofthe oppositeend, a pipe connected to one side of the-piston and ycominunicating with the cylinder on the other lside of the piston for admitting fluid under pressure to thev cylinder on that side ofthe piston, 'said pipe being concentrically located within the hollow piston rod to Vform a re sultant space between thepipe and the wall'of the'y rod, said rod being provided with an opening'coininunicating with said space and with the cylinder o'n the side of the piston opposite that with which said Vpipe communicates,V

means closingthe ends of said space, andv means for admitting fluid under pressure to said space.

scribed my name.

per press head carried bythe frame Work, a "platen mounted forreciprocation with. re-

spect to the frame work, aftable slidably mounted on the platen and normally disposed between the platen and the press head means for sliding said table laterally andv forwardly from its normal position to a projected positionat the front ofthe press and for returning said table to its normal posi- K tion, comprising a differential hydraulic cylinder rigidly carried by said table, a fiXed piston mounted in the cylinder, a piston rod` rigidly connected to the piston and to said platen at the rear end only of the press, a tiltable head provided with a trunnion jourswinging movements about a horizontal axis y y nalled in saidV stationary lupper head for s y and having ay die supporting surface normal-A ly disposed in parallelism with said table and facing the normal position thereof, and means for swinging said tiltable head from g its normal position to a position in which said die supporting surface faces the projectedv position of said slidable table, comprising a crank armon. said trunnion, a hydraulic cylinder fiXedto vsaidframe work and ar-f' ranged to operate a reciprocable piston rod'. f.

and connections between said crank-arm and said piston rod.v J e I 1l. In combinatiom-a support, a table slidably mounted thereon, a differentialhydrauliccylinder carried by said table, a piston In testimony whereof, l have hereunto subi e Liisiiiii iivuiaisnirr;

las Y 

